Letter-box alarm



(No Model.)

F. SNYDER. v LETTER BOX ALARM.

No. .402,282. Patented Apr. 80, 1889.A

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III, n IIIIIIII UNITED STATES yPATENT OFFICE.

FREDERICK SNYDER, OF`LANCASKTER, PENSYLVANIA.

LETTER-BOX ALARM.

SPECIFICATION forming part of Letters Patent No. 402,282, dated April 30, 1889.

Application filed October 2, 1888.

.To all whom, t may concern:

Be it known that I, FREDERICK SNYDER, a citizen of the Unit-ed States, residing at Lancaster, in the county of Lancaster and State of Pennsylvania, have invented certain new and useful Improvements in Letter-Box Alarms; and l do hereby declare the following to be a full, clear, and exact description such mechanism secure, as well as simple and strong. Y

To this end the said invention consists in the construction and combination of parts, hereinafter particularly set forth and claimed. In the accompanying drawings, Figure 1 I represents a vertical section from front to rear through the front of the letter-box and the alarm mechanism. Fig. 2 represents a rear elevation of the alarm mechanism and the plate to which it is attached. Figs. 3, 4, and 5 represent, respectively, in detail the hammer, the hammer-carrier, and the tripbar. Figs. 6 and 7 represent front and rear views of the front plate and the slide which covers and uncovers the opening therein.

A designates the front of the bor, having a front plate, B, secured on its face. In said plate is an opening, l), for receiving letters, which communicates with the usual downwardly-inclined passage, a, leading to the in'- terior of said box. The back of said front plate is recessed, as shown at b', to afford space for a slide-plate7 C, which may vbe moved upward in the guidewaydeftbetween said plate'and the front of the box. This upward motion uncovers the openingh and pas`v breadth the shank c of, finger-piece C fits said slot b2, so as to move easily up and down Serial No. 287,029. (No model.)

therein; but said handle is constructed with a broader front part or plate, c, which overlaps the sides and upper edge of said slot, affording an additional guide for slide-plate C, and hiding the opening through front plate, B, made by said slot, so that therecanbe no access to the interior of the box through this slot.

Slide-plate C is provided` on its rear face with a rigid inwardly-eXtending arm, C2, which passes through a vertical slot, A ,-in the front A of the letter-box, and also through a corresponding slot, CZ, of a plate, D, secured to the rear side of said box-front. The inner end of said arm C2 also enters a slot, c, similarly arranged to d, but shorter, in a longitudinallymovable trip-bar, E. This trip-bar is guided partly by an overlapping bent lug, d', of plate D and partly by the -sides of an openin'g, d2, through which said bar extends in a circumferential raised iiange or rim, D', of said plate. The lower end of said bar is enlarged and provided with a triangular opening, E2, which receives a stud, D2, on the plate D, and is partly overlapped by another bent lng, cl3, which serves to guide said lower end of said trip-bar and hold it in position to work. On one side this lower part is provided with a rigid nose, E3, which engages with a nose, f, of a hammer-carriage, F. A spring, G, wound on a stud, G', of said plate bears at one end against a stud, g, on said bar and at the other end against a stud, g', on said hammer-carriage, and operates to hold said noses together. Said hammer-carriage is pivoted at the middle on a stud, F, of plate D, and has at its lower end a tongue, f', eX- tending under bent lug di, so that said nose f may be guided and held in position thereby., On the other end of said hammer-carriage a hammer, Il, is pivoted, the tail of said hammer and the corresponding part of said hammer-carriage being curvegrooved to when it lifts trip-bar E. The engagement of the noses E3 and fcauses the hammer-carriage F to turn on its pivot against the resistance of spring G until the former nose slips by the latter one. The spring G then turns the hammer-carriage suddenly in the opposite direction; but said carriage is checked by the Contact of iixed lug di; with tongue j" before the hammer strikes the gong. The momentum of the hammer causes it to continue this motion independently against the resistance of Small spring h', and thus strike a cushioned or graduated blow instead of a violent one. The spring G simultaneously returns the tripbar E to its original position. The spring 7L does the like for the hammer, and the slideplate C falls by its own weight when released and closes opening b.

Having thus described my invention7 what I claim as new, and desire to secure by Letters Patent, is-

1. In combination with a letter-box, aslideplate which closes and opens the opening for letters and is provided withy a rigid rearwardly-extending arm, a trip-bar engaged by said arm, a hammer arranged to be drawn back by said trip-bar, and a spring for operating said hammer and replacing said tripbar, substantially as set forth.

2. A hammer, a pivoted carriage on whic it is pivoted, and a spring, h', between said hammer and carriage, in combination with a trip-bar having a nose which engages a nose on said hammer-carriage, a spring,G, engaging said carriage and trip-bar, and a slide-plate operating said trip-bar to turn the hammercarriage against the action of the spring G, substantially as set forth.

3. ln combination with alarm mechanism and a letter-box inclosing the same and having in its front a vertical slot and also a passage for letters, a front plate recessed on its inner face and provided with opening a, and a vertical slot communicating therewith, and a slide-plate which moves up and down in said recess to open and close opening b, said slide-plate being provided with a handle which extends forward through the vertical opening in said front plat-e, and an arm extending rearwardly through the vertical slot in the front of the box to engage with the alarm mechanism and operate it, for the purpose set forth.

4. The pivoted hammer carriage F, constructed with a nose, f, and a tongue, f', in

'combination with a trip-bar having a nose which engages and releases, as described, the nose aforesaid, a fixed lug which guides said noses and also limits the play of said hammer-carriage, a slide-plate arranged to raise the trip-bar for turning the hammer-carriage when said slide-plate is lifted, a hammer pivoted on said hammer-carriage to continue the stroke by momentum when the motion of said hammer-carriage ceases, and a spring in contact with said hammer which resists this independent motion of the latter and replaces it in its former position, substantially as set forth.

In testimony whereof I aiiix my signature in presence of two witnesses.

FREDERICK SNY DER.

Witnesses:

HENRY RUTH, DAVID G. XVILEY. 

